This invention relates in general to gas discharge fluorescent devices, and in particular to a cold cathode fluorescent lamp (CCFL) system that is particularly versatile and useful for illumination applications, such as for illuminating a chamber in a building.
CCFL illumination systems are advantageous over hot cathode fluorescent lamps (HCFL) for many reasons and operates using mechanisms that are different from HCFL. The differences between CCFL systems and HCFL systems are explained in more detail in United States Patent Application Publication U.S. 2005/0275351 which is incorporated herein by reference.
As the world enters a period where energy costs will continually increase for the foreseeable future it is imperative to reduce the amount of energy that is consumed by lighting. As known to those skilled in the art, incandescent lighting is notoriously inefficient for lighting purposes. While HCFLs have been widely used to replace incandescent lamps for lighting purposes, the HCFLs are not as flexible as compared to CCFL lighting systems. For example, it may be difficult or impossible to adjust the intensity of light emitted by HCFL lighting systems for different lighting requirements, such as in a dimming operation. It is therefore desirable to provide an improved lighting systems, such as ones using CCFLs, which have better characteristics and flexibility compared to prior lighting systems.
One of the problems encountered in CCFL lighting systems is the fact that heat sensitive electronic components in the CCFL lighting system can be adversely affected by the heat generated by the CCFL lighting element itself and the lifetime of these electronic components may be reduced, thereby also reducing the useful life of the CCFL lighting system. Another problem encountered when CCFLs are used for general lighting is the need to include a converter for converting power from utility power line. This renders the CCFL device bulky and hard to use for lighting purposes, such as in lighting fixtures. It is therefore desirable to provide an improved CCFL lighting system where the above-described disadvantages are avoided or alleviated.
With the different roles lighting is playing in every day life, it is desirable to be able to adjust the intensity and color temperature of lighting applications. However, as noted above, it is difficult to use lamps such as HCFLs for lighting that uses dimming or adjustment of color temperature. The lighting fixtures presently available are also not adapted for lighting operations that permit the changing of color temperature. It is thus desirable to provide a lighting fixture that enables both dimming and the adjustment of color temperature, while also achieving high energy efficiency.